Chuck



H. C. ELVERS.

CHUCK.

APPLICATION FILED FEB. 12, 1921.

Patented Feu-14, 1922..

2 SHEETS-SHEET I.

H. C. ELVERS.`

CHUCK.

APPLICATION FILED FEB. I2, 1921.

Patented Feb. 14

1922. 2 SHEETS-SHEET 2.

KNQNI NI RM.

Wme l UNl'lhlB PATENT OFFICE.

HANS C. ELVERS, GF IJADESON, XVESCONSIN, ASSIGNOR TO GSI-IOLT MACHINECOM- PANY, OF IVIADBSON, W'ISCQNSIN, A CORPORATIGN OF WISCONSIN.

CHUCK.

Application filed February 12, 1921.

To all wko/m, t may concern.'

Be it known that I, HANS- C. Envnns, a citizen of the United States,residing at Madison, in the county of Dane and State of Wisconsin, haveinvented certain new and useful Improvements in Chucks, ot which thefollowing is a specification.

This invention relates to improvements in chucks for ,lathes and similarmachines employing chucks, and, as to its principaleatures, relates tothat type of chucks wherein the chuck jaws are actuated between grippingand release positions by elbow levers mounted in the chuck body.

One object ot the present invention is to provide a chuck constructionof this general type which shall make possible the disengagement of theelbow levers from the jaw bases to permit withdrawal oit the latter fromthe chuck head by a simple outward sliding` movement, and withoutnecessitating any partial dismantling of the structure.

A turther object ot the invention is to provide an improved pneumaticoperating mechanism for the elbow levers which in turn eiiect the workgripping movements of the chuck jaws; this mechanism, according to thepresent invention, taking the form ot an annular `piston mounted in thechuck head and operated by compressed air in both directions, saidpiston having a hub suitably slotted to receive the radial arms of theelbow levers. y

Other objects and advantages of the invention will be apparent to thoseskilled in the art as the invention becomes better understood byreference to the following detailed description, taken in connectionwith ther' accompanying drawings, wherein l have illustrated onepractical and approved embodiment of the invention, and in which- 'Fig 1is a front elevation of a chuckhead embodying my present invention;

Fig. 2 is a .diametric section on the line .2-2 lot F ig. 1, showingtheV elbow levers operatively engaged with the bases of the jaws; y

Fig. 3 is a fragmentary sectional view, showing the lower portion ofFig. 2 with the elbow levers disengaged from the jaw bases to permitremoval of the latter from the slideways of the chuck head; c

Fig.` 4 is a plan view oit' the annular lever carrying block which ismounted in an an- Specicaton or Letters Patent.

Patented Feb. 14, 1922.

Serial No. 444,335.

nular chamber ot the head and is adjusted inwardly to shift the jawengaging lever arms cnt of engagement with the jaws; and

Fig. 5 is a sectional detail on the line 5-5 of' Fig. 1, illustratingthe lever block adjusting means.

Since the present invention relates wholly to improvements in the chuckhead and parts carried thereby, I have not herein deemed it necessary toillustrate in full the spindle, spindle bearings, and pneumatic pressurecontrolling devices; but I have shown at 6 the inner end of a tubularspindle, to which is attached the back-plate 7 of the chuck, this latterhaving mounted thereon the chuck body designated as an entirety by 8.The chuck body 8 is formed with the usual radial slideways 9, in whichlatter are mounted the jaw bases 10, carrying jaws 11 adjustably securedthereto by counter-sunk cap screws 12.

rihe chuck head 8 is cored to provide an annular chamber 13 that isco-axial with the chuck head; and in this chamber is slidably ifitted anannular ring or block 14, shown in isolated detail in Fig. 4. The outerface or' the block 14, is provided at equal spaced intervals with radialslots 15 corresponding in number and location to the slideways 9 of thechuck head and lying directly Lbehind the` latter. Fulcruined on pivot'pins 16 which extend crosswise of the slots 15 are a series oit-elbowlevers, each of which has a short arm 17, that extends through thebottomof the slideway 9 and is operatively engaged with the jaw base 10, and along arm 18 that extends radially of the chuck head through a slot 19formed in a suitably packed ring 20 that forms the outer wall of theannular chamber 13.

`When the annular block 14 is in its voutermost position illustratedin-Fig. 2, the short arm 1'? oi"- the elbow lever is operatively engagedwith the jaw base 10.r

adjustment of the annular block 14 l'have' .an annular piston 80.

o long arms 18 of` the elbow levers.

provided the simple means illustrated in Figs. 1 and 5, wherein 21designates a screw bolt slidably engaged witha countersunk hole 22,termed in the chuck head, the inner portion et' the screw bolt having athread 23 engaged with a tapped hole 241 in the block 141.. By turningthe bolt 21, by the application of a screw driver, in one direction, theblock 14C is drawn outwardly into engagement with the outer wall ci itschamber 13, as shown in Fig. 9J, and.

'and the thrust pins Q7 are, by the applicaf if, -.',.A',.( a tion oJr ascrew din ei, telcel inwaidl Auntil the block 111 has been shifted tothe bottom of its chamber 13. This, as above stated, disengages theelbow levers :from the chuck aws and allows the latter to be withdrawnby a simple outward sliding movement. y

To reestablish the engagement oit' the levers with the jaws, the thrustpins 27 are backed out, and the screw bolts 21 are then screwedinwardly, thereby restoring `the parts to the relative positionsillustrated in Fig. 2.

Referring now to that feature of the invention which relates to the.improved pneumatic lever operating mechanism, encircling the chamber 13and block 14 is a second annular chamber 29, constituting an an` nularcylinder, in which is slidably mounted This piston 30 is formed with anoutwardly extending sleeve or hub 31 that is slidably engaged with thering 2l) `and provided with radial slots into which extend the outerends of the To provide sullicient play for the hub 31 of the 'piston onits outward travel, the annular channel in which the hub 31 is mountedes;- tends outwardly to a point somewhat beyond the bottoms of theslideways 9, as shown at 33 in Fig. 2; and each et the jaw bases 10 isprovided on its inner side witha transverse slot zl/l registering withkthe outer portion 33 elA said channel, the

slots 34- being of suilicient width to permit the travel of the jawscaused by the swinging movements of the elbow levers.

Compressed air from a suitable source is supplied to and exhausted fromthe forward face of the piston 30 through a pipe 35 and ducts 36, 37 and38, drilled in the back-plate 7 and chuck body 8; and compressed air issupplied to andr exhausted from the rear side of the piston 30 through apipo 39, and ducts 410 and 41 drilled in the back-plate.

1With the parts in the relative position shown in Fig. 2, and with thework suitably chucked in the jaws, the latter are forced inwardly intotight holding engagement with the work by admitting compressed airthrough the pipe 39 to the rear of the piston 30 and simultaneouslyexhausting through the pipe 35 the air from the front ot the piston.Manifestly, when the work is to be released from the chuck, or when apiece of work is to be internally chucked by the outer ends of the jaws,the latter are forced outwardly by admitting the compressed air throughthe pipe 35 to the front side of the piston and simultaneouslyexhausting the air from the rear side of the piston through'the pipe 39.

It is believed that the foregoing description, taken in connection withthe drawings, will make clear to persons skilled in the art the novelstructural features and the mechanical principles upon which theinvention is based; and while I have herein set forth one practical andoperative embodiment of the principles involved, it should be understoodthat the structural features may be considerably modified in detailwithout departing from the principles or sacrificing any of theadvantages of the invention. Hence, I reserve all such variations andmodifications as fall within the spirit and purview of the appendedclaims.

I claim:

1. A chuck having a body portion formed with radial slideways and with achamber in rear of saidslideways, a block mounted in said chamber andmovable between the front and rear walls thereof, levers pivoted in saidblock, jaw carriers engaged withv said slidewa-ys and slotted to engagewith said levers, and means for shifting said block in said chamber tothereby engage said levers with. and disengage them from,`

said jaw carriers.

A 2. A chuck having a body portion formed with radial slideways and withan annular chamber in rear of said slideways, an annular block `mountedin said chamber and slidable between the front and rear walls thereof.radially disposed elbow levers pivby engage said levers with, anddisengage them from, said jaw carriers.

3. A chuck having a body portion formed i with radial slideways and.with an annular chamber in rear of said slideways, an annular bleekmounted 1n said chamber and slidable between the front and rear wallsthereof, radially disposed elbow levers pivoted in said block, jawcarriers engaged with said slideways and slotted on their undcrsides toarticulate with the forwardly extending arms of said elbow levers, drawbolts mounted in said body portion and having threaded engagement withsaid block to thereby shift the latter outwardly to, and secure it in, aposition wherein said levers engage with the slots of said jaw carriers,and thrust bolts having threaded engagement with said body portion andbearing at their inner ends on said block to thereby shift the latterinwardly to, and secure it in, a position wherein said levers aredisengaged from said jaw carriers.

at. A chuck having a body portion formed with radial slideways and withan annular cylinder in rear of said slideways, jaws carriers mounted insaid slideways, elbow levers pivoted in said body portion and eachhaving a forwardly extending arm operatively en# gaged with one of saidjaw carriers and an outwardly extending radial arm, an annular pistonfitted to said cylinder, said piston having a hub encircling said leversand operatively engaged with the outer ends of the radial arms of thelatter, and means for admitting and exhausting motive fluid to and fromthe opposite faces of said piston.

5. A chuck having a body portion formed with radial slideways and withan annular cylinder in rear of said slideways, jaw carriers mounted insaid slideways, elbow levers pivoted in said body portion and havingforwardly extending arms articulated with said jaw carriers near theinner ends of the latter, and outwardly extending radial arms, anannular piston fitted to said cylinder, said piston having a sleeve-likehub provided with transverse slots receiving the outer ends of theradial arms of said levers, and means for admitting and exhaustingmotive {iuid to and from the opposite faces of said piston.

6. A chuck having a body portion formed with radial slideways, a chamberin rear of said slideways, and an annular cylinder encircling saidchamber, a block mounted in said chamber and shiftable between the frontand rear walls thereof, radially disposed elbow levers pivoted in saidblock, jaw carriers engaged with said slideways and slotted to engagewith forwardly extending arms of said levers, means for'shifting saidblock in said chamber to thereby engage said levers with, and disengagethem from, said jaw carriers, an annular piston fitted to said cylinder,said piston having a sleevelike hub encircling said block and slotted toengage with the other arms of said levers, and means for admitting andexhausting motive Huid to and from theopposite faces of said piston.

HANS C. ELVERS.

